The Bangalore Water Supply and Sewerage Board (BWSSB) has floated tenders for nine new sewage treatment plants (STPs) in the city that will collectively treat 535 million liters of sewage per day (MLD).
This will take the total sewage treatment capacity of the city to 1883.5 MLD when completed. Despite this, the city will still be far behind to reach the target of over 2,740 MLD. Currently, the city generates 2,120 MLD of sewage every day and another 620 MLD is expected with the expansion of Cauvery V Stage.
“Six of these STPs will generate electricity through biogas. and the tertiary treated sludge will be converted into manure and sold. Both will bring income to the board. They will also have an odor control unit to help reduce the unpleasant smell that usually emanates from the STPs,” said V. Ramprasath Manohar, Chairman, BWSSB.
Energy production
Six STPs with a processing capacity of 50 MLD or more will generate up to 4 MW power through biogas. This is a new technology being introduced in the city. Only Hebbal Valley and Vrishabhavati STPs currently have this technology. This energy is consumed locally to operate the power plant, which is designed so that at least half of the required energy is covered by biogas. The electricity bill is one of the biggest components of STP operations, which will reduce the board’s dependence on the Bescom network and save money, officials said.
Ecological
For the first time, these STPs will be equipped with latest anaerobic technologies like A2O Technology with Tertiary Treatment Unit – Disc Filter which will help meet the output parameters with the new norms of Central Pollution Control Board and National Green Tribunal. Disc filters as tertiary treatment units are more environmentally friendly than conventional treatment units such as multimedia units or sand filter beds. The sludge produced by these plants is treated and safe for use as manure. BWSSB also intends to sell manure to earn, BWSSB sources said.
Financing
The nine STPs together will cost ₹2,071.21 crore.
Sources said while the state government and BWSSB will each contribute 25% of the cost, the rest will be financed through a loan. BWSSB will soon seek Expression of Interest (EoI) from financial institutions for the loan.
Published – 06 Nov 2025 21:12 IST
